There was a time not that long ago when “nut” and “milk” didn’t go together in the same sentence.

Now, plant-based alternatives to dairy milk are all the rage.

Options like almond, coconut, rice and soy milk have been around for years, serving people with lactose intolerance or other dairy allergies. But a quick trip down any dairy aisle reveals an expanding array of newer options — from oat, cashew, flax and hemp milk to pecan and even quinoa milk.

These new alternatives are so popular, they have grown by 61 percent over the past five years, according to data collected by research firm Mintel. In 2017, the firm estimated that plant-based milk sales reached $2.11 billion, while sales of dairy milk fell 15 percent in the previous five years.

Sales have dropped to almost half what they were in the 1970s, when dairy milk peaked as a staple in American homes.

So why the backlash against cow’s milk? The answer is two-fold, Tampa Bay area nutritionists say.

“People who are more health-conscious tend to go in the plant-based direction,” said Nan Jensen, a licensed nutritionist in Pinellas County. “That is the main reason. But there are people who are passionate about the ethical treatment of animals or can’t tolerate dairy. There are a variety of options and they are gaining in popularity. But people should ask themselves why they’re consuming this product and what are the benefits.”

It’s hard to say if lactose intolerance is on the rise, Jensen said. But medical technology has certainly improved, making it easier to pinpoint food allergies, which may be causing some people to steer clear of cow’s milk.

“We’re just better at diagnosing and detecting these types of things. Some people may have issues with cheese and yogurts, but not milk,” she said. “But some people opt in because they just think it’s healthier. Like gluten-free diets. Plenty of people buy those products not because they need to.”

Before ditching cow’s milk, consumers should consider that not all “milks” are created equal.

Cow’s milk, for example, has high nutritional value because it contains calcium, vitamin D and protein. Milk “imitators,” as some dietitians call the plant-based alternatives, aren’t necessarily fortified with those same nutrients, and they don’t all offer the same levels.

“Dairy is one of these things that tends to get a bad rep,” said Hillary Willy, a licensed dietitian at the Bariatric & Metabolic Institute at AdventHealth Tampa. “There’s so much misinformation about what’s healthy and what’s not in the public. Dairy still has a lot of great nutrients and contributes to a healthy, well-balanced daily diet.”

Still, one in five Americans say they are consuming less dairy for health reasons, the Mintel research shows.

“People should really read the food label when considering a nondairy alternative,” Willy said. “A lot of times these plant-based milks will be fortified with calcium and vitamin D, but they’ll also have flavors or sweeteners, too. Don’t just assume the nutrition is there.”

The $35.5 billion U.S. dairy industry has struggled in recent years, and the rise of these plant-based alternatives hasn’t helped. Dairy farmers have tried to push lawmakers and the U.S. Food and Drug Administration to force plant-milk manufacturers to call themselves something other than milk.

“An almond doesn’t lactate, I will confess,” FDA Commissioner Scott Gottlieb said when questioned on the topic last summer.

The effects on farmers and the dairy industry can be felt locally, too, said nutritionist and Florida Beef Council member Sarah Krieger. Hillsborough County’s last dairy farm shuttered in 2017, a time far removed from when 60-plus farms operated in the rural areas of Tampa before real estate developers began buying up the land and turning it into subdivisions.

“I always ask my clients why they want to drink something other than dairy,” said Krieger, who runs her own dietary business, Healthy Lifestyles Tampa Bay. “People have been drinking milk for thousands of years. So many people want to eat natural foods, and dairy milk is about as natural as it gets.”

The dairy industry has also created lactose-free products for people with dairy issues. And they’ve developed a type of cow’s milk called A2 that is easier for lactose-intolerant people to digest, Krieger said.

But in most cases, consumers can find similar taste, consistency and nutritional value in nut, oat or other plant-based milks.

The trend doesn’t appear to be going away.

Consumers, however, must be willing to pay more for it. In some cases, nut or oat milk can be two to three times the cost of a gallon of whole or skim cow’s milk.

“Plant milks aren’t subsidized like cow’s milk, and are higher in price per fluid ounce,” Jensen said. “It might impact some on a budget, especially since they tend to be offered at specialty stores like Whole Foods.”